The ability to measure location-specific brain signals is beneficial for medical and diagnostic applications as well as for scientific research. From a diagnostic point of view, measuring brain signals helps to ascertain brain activity related to abnormal brain function, to monitor spatial and/or temporal progression of brain disease, and to aid surgical or nonsurgical intervention by localizing disease-sites in the brain. From a scientific perspective, the ability to measure and study brain signals facilitates scientific research aimed at understanding the structure and function of the human brain.